Multiple-filament incandescent lamp



L. CAMMEN. MULTHLE HLAMENT INCANDESCENT LAMP,

APPLICATION FILED APR-35,1918- Patented June 13, 1922.

Fig. I.

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llll I\ llllllll/W Invent or m w m m ma a fi. S m%w m LEON CAMMEN, 01' NEW YORK, N. Y., ASSIGNOR TO GENERAL ELECTRIC COMPA'N' Y, A.

CORPORATION OF NEW YORK.

HULTIPLE-FILAMENT INCANDESCENT LAMP.

Application filed April 15,

To all whom it may concern:

Be it 'known that I, LEON CAMMEN, a citizen of the United States, residing at New York city, in the borough of Manhattan, State of New York, have invented certain new and useful Improvements in Multiple- Filament Incandescent Lamps, of which the following is a specification.

The object of my invention is to provide a multiple filament lamp having a base of the usual bayonet type and suitable for use in any of the standard sockets commonly used on automobiles and provided with a simple meansoperable by the fingers, if necessary, for putting a reserve filament into circuit. A further object is to provide forlamps of this type a base which can be easily and cheaply manufactured from stamped or pressed parts and which costs very little more than the standard bases now in use. Another object is to improve and cheapen the construction of multiple filament lamps suitable for use in standard sockets.

' To these ends I provide the base .with metal clips of such a form that they can be stamped out in large quantities at a very low cost and mounted on the base with; very httle expense in addition to that of mounting the usual terminals, and connected to the-reserve filament in such a way that whenever desired the reserve filament can be put in circuit by closing the circuit through the clips, preferably by grasping and pulling from between the clips a strip of insulation, such as fiberor paper, which normally holds the clips apart. The strip of paper can be pulled out with the fingers, no special tools or expert manipulation being required.

y invention will best be understood from the accompanying drawing in which merely for purposes of illustration I have shown one of the various forms in which it may be em- 7 bodied andin which Fig. 1 is a phantom view in perspective ofa lamp embodying one form of my invention Fig. 2 is a longitudinal section of the base along the line 2-2; Fig. 3 is a longitudinal section of the base along the line 3-3; and Fig. 4 is a diagram of the filaments and the circuits.

In the particular form of lamp illustrated in the drawing the bulb 10 contains two filaments 11 and 12 which have their adjacent inner ends connected to a lead 13 and the and 15. The lamp has a/ bayonet base 16 consisting of a metal shell Specification of Letters Patent.

circuit without the use Patented June 13'. 1922. 1918. Serial no. 228,629.

with an insulating web 17 having a fiat end with a recess or opening 18 in it. A. circuit terminal 19 of the usual form is connected through the lead" 13 to the adjoining ends of the filaments l1 and 12, and the other terminal 20 is connected to t e outer end of the filament 11. With the connections just described, the filament 11 will be lighted when the lamp is inserted in the socket.

In order that "the reserve filament 12 may be brought .into circuit whenever desired I provide means adapted for manipulation-by the fingers for connecting the outer end of the filament 12 to terminal 20 to put the reserve filament 12 into circuit. The particular form of means illustrated in the drawings comprises two spring clips 21 and 22 mounted on the insulating web 17 between the terminals 19 and 20 and projecting into the central recess 18 by which they are protee-ted. These spring ,clips are normally separated by a strip 23 of fiber, paper, or any other suitable insulating material. This strip projects from the base far enough so that the end can be seized and the insulating strip withdrawn whenever desired. The clip 21 is electrically a part of the terminal 20, this result being accomplished by spreading the solder 24 to bridge the gap between the terminal and the clip when the lead 15 is soldered to the terminal.

When the lamp is first inserted in the socket with the insulating strip 23 in the position shown in Fig. l, the filament 11 is lighted. The reserve filament 12 can be inserted in the circuit merely by withdrawing the insulating strip 23, whereupon clips 21 and 22 spring together and establish a circuit from the terminal 19 through the filament 12 to the terminal 20. The driver of the automobile can withdraw the strip 23 with his fingers, so that the reserve filament can be put into circuit without the use of tools'and with very little trouble.

It will be seen that I provide a multiple filament lamp with a standard bayonet base and a reserve filament which can be put into of tools or the manipulation of small or delicate parts. The clips 21 and 22 can be stamped out in large numbers at a very low cost and can be set in the web 17 of the base at the same time and inthe same manner as the terminals 19 and 20, so that the additional expense is very slight. The-metallic connection between the terminal 20 and the clip 21 is made at practically no extra expense when the lead 13 is soldered to the terminal 19.

The conducting connection between the terminal 20 and the lead 14; can be established in other ways than by the withdrawal of the insulating strip 23 and I therefore do not wish to be restricted to the precise arrangement disclosed, but intend to cover all modifications within the scope of the annexed claims.

What I claim as new and desire to secure by Letters Patent of the United States, is

1. An incamlescent electric. lamp having two supply terminals and two filaments, one permanently connected in circuit with said terminals and the other normally kept out of circuit, and means comprising cooperating contacts and a removable insulating member between said contacts for holding them separated and vrendered operative by the removal of said insulating member from betweenthe contacts to chise the circuit through said auxiliary filament.

- 2. A combination with an incandescent electric lamp having a main filament of an auxiliary filament normally'out of circuit, and means comprising cooperating contacts and a removable strip of insulation between said contacts and responsive to the removal of said strip of insulation for connecting said auxiliary filament in circuit.

3. An incandescent electric lamp having two supply terminals and a main filament connected thereto, an auxiliary filament with one end connected to one of said terminals, :1 third terminal for the other end of said auxiliary filament, and an electrical bridge between said third terminal and one of the other terminals normally held open by a stripcf insulation removable at will to close said bridge and connect said auxiliary filament into circuit.

4. In an incandescent lamp :1 base having a fiat end with a central recess therein, a main contact mounted on said end and having electrically connected to it a spring clip projecting into said recess, a cooperating spring clip mounted on said base to project into said recess and normally held out of contact with the other spring clip by insulation readily removable by the fingers, a reserve filament connected to said cooperating spring clip and said main contact, a second main contact mounted on the end of said base, and a main filament connected to said main contacts.

5. A base for a multiple filament lamp comprising a cylindrical web having a recessin one end, two main contacts-mounted on said end on opposite sides of said recess, a pair of spring clips mounted on said end opposite each other and between said mam tel minals to project into said recess and biased to move into contact with each other, and a strip of insulation between said clips for holding them separated and having its end projecting to permit it to be readily seizedv and removed from between said clips.

In witness whereof. I have hereunto set my hand this 12th day of April, 1918.

LEON CAMMEN. 

